If you own a flatbed truck, you know the struggle of keeping tools and gear organized and secure. Side boxes are essential for maximizing storage without sacrificing bed space. We researched and compared seven top-rated models based on manufacturer specs, industry standards, and aggregated owner feedback. Our evaluation focuses on durability, security, ease of installation, and real-world performance to help you choose the best side box for your needs.
| Photo | Product | Score | Buy |
|---|---|---|---|
|
🚗
|
Weather Guard Saddle Box Best Overall Aluminum construction, 18 cu ft capacity, rotary lock system |
9.2 | 🛒 Check Price |
|
🚗
|
UWS ECONO Saddle Box Best Value Steel construction, 16 cu ft capacity, paddle latch |
8.7 | 🛒 Check Price |
|
🚗
|
Dee Zee Heavy Duty Side Box Most Durable Aluminum, 20 cu ft capacity, push-button lock |
9.0 | 🛒 Check Price |
|
🚗
|
Rugged Ridge Saddle Box Best for Off-Road Steel, 14 cu ft capacity, T-handle lock |
8.4 | 🛒 Check Price |
|
🚗
|
Buyers Products Aluminum Side Box Lightweight Choice Aluminum, 12 cu ft capacity, slam latch |
8.1 | 🛒 Check Price |
|
🚗
|
Kobalt Steel Saddle Box Budget Pick Steel, 15 cu ft capacity, key lock |
7.8 | 🛒 Check Price |
|
🚗
|
TruckCraft Aluminum Side Box Compact Option Aluminum, 10 cu ft capacity, paddle latch |
7.3 | 🛒 Check Price |
1. Weather Guard Saddle Box: Best Overall
The Weather Guard Saddle Box is a top performer in our evaluation, offering a robust aluminum body that holds up well against the elements. Based on owner feedback and the spec sheet, the rotary lock system provides reliable security, and the diamond-plate texture minimizes scratches. However, the price is premium, and some users noted that the box can be heavy to install solo.
If you need maximum durability and are willing to invest, this is an excellent choice. However, budget-conscious buyers or those who prefer lighter materials might want to explore other options. It is best suited for heavy-duty use and professional tradespeople.
- Rugged diamond-plate aluminum with stainless steel hardware resists rust
- Low-profile design maintains visibility and allows bed access
- Rotary latches with keyed-alike locks for security
Pros: Excellent build quality and weather resistance; Smooth-operating lid with gas struts
Cons: Higher price point than some competitors
2. UWS ECONO Saddle Box: Best Value
The UWS ECONO Saddle Box offers a solid steel build at a more accessible price point. We compared it against similar models and found that while it lacks the premium feel of aluminum, it provides reliable storage for everyday use. Owner feedback highlights the easy installation and the secure paddle latch, though some noted that the paint can scratch over time, exposing the steel to potential rust.
This box is ideal for DIYers and light commercial use who want a functional side box without breaking the bank. However, if you work in a salt-heavy environment or need all-weather resilience, consider an aluminum alternative.
- Heavy-duty steel with black powder coat finish
- Paddle latch with lock for quick access
- Reinforced lid for added strength
Pros: Affordable without sacrificing basic durability; Easy to install with included mounting hardware
Cons: Steel prone to rust if paint is chipped
3. Dee Zee Heavy Duty Side Box: Most Durable
The Dee Zee Heavy Duty Side Box impressed us with its robust construction and high weight capacity. Based on the manufacturer specifications, the continuous weld seams and thick aluminum ensure long-term durability. Owner reviews consistently praise its ability to withstand rough job site conditions. However, the box is quite heavy, and some users found the push-button lock less intuitive than a traditional latch.
This is a top choice for professionals who demand maximum durability and are okay with a heavier box. If you frequently need to remove the box or prioritize lightweight design, you might prefer a different model.
- Thick gauge aluminum with continuous weld seams
- Push-button lock with key override
- Built-in lid organizer for small parts
Pros: Exceptional build quality and rigidity; Good internal organization features
Cons: Heavy weight makes installation a two-person job
4. Rugged Ridge Saddle Box: Best for Off-Road
The Rugged Ridge Saddle Box is built for tough environments, with a textured finish that hides scratches from off-road use. In our evaluation, the steel construction and T-handle lock offer solid security, though the interior space is more limited. Owner feedback from off-road enthusiasts highlights its ability to keep gear dry, but some wished for a larger volume.
This box is best for off-roaders and overlanders who need a compact, durable side box that can take a beating. If you need to store large tools or equipment, consider a larger capacity model.
- Textured black powder coat for off-road abuse
- T-handle lock with dust cover
- Mounts flush to bed rail
Pros: Rugged design resists impacts and debris; Low profile does not obstruct rear view
Cons: Smaller capacity than many competitors
5. Buyers Products Aluminum Side Box: Lightweight Choice
The Buyers Products Aluminum Side Box is one of the lightest options we evaluated, making it a good choice for those who frequently remove their side boxes. Based on the spec sheet, the slam latch is convenient, but some owners reported that the latch alignment can be finicky over time. The aluminum is corrosion-resistant, but the thinner gauge means it is less impact-resistant than heavier models.
This box suits users who prioritize easy installation and low weight, such as weekend warriors or those with limited help. However, for heavy-duty commercial use, a sturdier box is recommended.
- Lightweight aluminum reduces truck load
- Slam latch for quick one-hand operation
- Painted with UV-resistant coating
Pros: Easy to install due to low weight; Corrosion-resistant aluminum
Cons: Thinner gauge may dent under heavy load
6. Kobalt Steel Saddle Box: Budget Pick
The Kobalt Steel Saddle Box is a budget-friendly option that provides basic storage for flatbed trucks. We compared it against other steel boxes and found that while it offers a good capacity-to-price ratio, the build quality is not as high. Owner feedback indicates that the paint is prone to chipping, and the lid can warp in extreme heat, compromising the seal.
This box is suitable for occasional use or for those on a tight budget. If you need a long-term durable solution, it is worth investing in a higher-end model.
- Economical steel construction with black finish
- Key lock for basic security
- Pre-drilled mounting holes for easy install
Pros: Very affordable price point; Decent storage volume for the cost
Cons: Paint can chip easily leading to rust; Lid may warp over time under heavy sun
7. TruckCraft Aluminum Side Box: Compact Option
The TruckCraft Aluminum Side Box is the smallest in our lineup, designed for compact flatbeds or those who only need minimal storage. Based on owner feedback, the aluminum body holds up well against rust, but the paddle latch mechanism has been criticized for its lack of robustness. The box is easy to install due to its low weight, but the storage space is limited.
This box is best for those with limited bed space or who only need to store small items like tie-downs and basic tools. If you require more capacity or a sturdier latch, look elsewhere.
- Compact size fits smaller flatbeds
- Paddle latch with lock
- Lightweight and easy to handle
Pros: Great for tight spaces or single-cab trucks; Aluminum resists corrosion
Cons: Limited capacity may not suit all users; Latch feels flimsy according to some owners
Frequently Asked Questions
What size side box do I need for my flatbed?
Measure the length and width of your flatbed’s side rail. Common sizes range from 10 to 20 cubic feet. Consider the items you plan to store: if you carry long tools, a larger box is better. Also check the weight capacity and ensure it does not exceed your truck’s payload limits.
Are aluminum side boxes better than steel?
Aluminum is lighter and resists rust, making it ideal for humid or coastal areas. Steel is generally stronger and more affordable but can rust if the paint chips. For heavy-duty use, steel may be more durable; for weight savings and corrosion resistance, aluminum is better.
How do I install a side box on a flatbed?
Most side boxes come with mounting brackets and hardware. You typically drill holes into the flatbed’s side rail and bolt the box in place. Ensure the box is level and securely fastened. Some models offer clamp-on installation without drilling. Always follow the manufacturer’s instructions.
Can side boxes be locked for security?
Yes, all side boxes we reviewed include locks. Common types are key locks, paddle latches with locks, and rotary latches. For high security, choose a box with a robust locking mechanism and consider adding a padlock. Keep in mind that no lock is completely theft-proof, but a good lock deters casual thieves.
Will a side box affect my truck's fuel economy?
Adding a side box increases weight and wind resistance, which can slightly reduce fuel economy. The impact is usually minimal for most trucks. Aluminum boxes are lighter and cause less drag than steel. If fuel economy is a major concern, choose a lightweight, aerodynamic design.
Our Verdict
After researching and comparing the top models, the Weather Guard Saddle Box earns our top pick for its excellent build quality, security, and weather resistance. For a more budget-friendly option that still offers solid performance, the UWS ECONO Saddle Box is our runner up. Consider your specific needs for capacity, material, and budget when making your final choice.
Last reviewed and spec-checked: June 4, 2026. We re-check our picks and listings periodically.
